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In the present paper a theoretical model for the analysis of compound crank axle is presented. It is based on the set of equilibrium, constitutive and congruence equations of the axle; to this aim, the cross-member is described by its stiffness matrix, the longitudinal arms are assumed as rigid and the bearing which connects the axle to the body as ideal. For this configuration, a closed form solution for the elastokinematic analysis is obtained in the small displacements field, for the pure roll condition. This can be summarized by the knowledge of the position, in a 3D space, of the instantaneous axis of rotation of each wheel; it is shown how the instantaneous axis of rotation is determined by both the axle geometry and the stiffness properties of the cross member. An iterative procedure has been also developed for the large displacement analysis. Results, in terms of camber and toe angle alteration, are discussed in comparison with those obtained by finite element analyses.

Purpose: This study analyzes the effect of front seat performance on occupant injury in rear crashes where there is a 2nd row passenger seated behind the front occupant. Methods: The study was carried out for rear impact crashes in the 1991–2006 NASS-CDS. Only cases where there was a 2nd row occupant seated behind an occupied front seat were chosen. Serious injury (MAIS 3+F) was determined for the front and 2nd row occupants. The performance of the front seat was determined using eight NASS-CDS investigator categories, including no failure, seat failure of the adjuster, seatback or track-anchor and seat deformation by the occupant or intrusion. The rear crashes were subdivided into four severities (<15, 15–25, 25–45 and >45 mph). The risk for serious injury was determined for each category of seat performance. Next, individual cases were reviewed from the online NASS electronic files to better understand the determination of seat performance by the NASS-CDS investigators.

Automotive manufacturers often rely upon features such as automatic locking to enhance the security and crashworthiness of doors in rollover accidents. This can be verified in warnings conveyed to vehicle owners through some owner's manuals. At the present time, there are no requirements on the dynamic performance of door locking systems within the Federal Motor Vehicle Safety Standards (FMVSS), although some static inertia requirements exist for latch systems. Field accident investigation and laboratory testing has revealed that some locked doors can self-unlock in rollover accidents when a vehicle sustains a roof impact. Using standard laboratory shock testing machinery, the acceleration boundaries required to trigger self-unlocking have been mapped for some sample doors. Impact pulses of surprisingly low levels of acceleration, when combined with sufficient duration have been found to trigger this response.

An identification based approach to the design and implementation of a Kalman-filter feedback control method for the transient chassis dynamometer is presented. The requirements for torque controllers for high speed transient chassis dynamometers for road-load simulation are discussed. A common significant problem with feedback control in the conventional transient chassis dynamometer is due to resonances arising from the structural dynamics especially in the load centre linkage. A Kalman filter based filter and control method is proposed to address this issue and to provide significantly enhanced performance over that achieved by current controllers. Particular attention is paid to obtaining relative stability margins in all filter and control loops for robust torque feedback control by the use of H-infinity methods. The filter and controller designs are based on easily implementable identification methods.

Three-dimensional CFD was used to optimize the torus section and stator blade shape, and newly developed stator blades were also employed to develop the fluid flow channels for a thin type torque converter with a flattening ratio of 50%, while maintaining torque converter performance. A multi-plate lock-up clutch with heat-resistant performance approximately twice that of a conventional single-plate lock-up clutch has been positioned in the space created by the use of these new fluid flow channels. The developed Super Ultra Flat torque converter with multi-plate lock-up clutch enables all-area LC control without increasing the overall width compared to the previous torque converter, and can be fitted in an FF vehicle. As a result, in real-world driving, the new system increased fuel efficiency by approximately 3% in US06 mode, and enabled a more direct driving feeling by shortening the time from 0 to 100 km/h at 100% throttle acceleration by 0.2 s, etc.

Digital filters are used in many automotive applications ranging from identification and conditioning of signals in an engine controller to digital radio receivers. Often these filters are implemented in fixed point for reasons such as throughput or cost. Selecting a fixed-point implementation requires trading off behavioral performance for available resources on the embedded processor. In addition, many of these filters must support calibration at processor startup or run time. Hence the selected implementation must meet the behavioral requirements for a set of digital filters. A common example application is audio processing to optimize cabin acoustics. In this case, the embedded audio processor queries the vehicle identification over the vehicle network then selects a bank of digital filters which are calibrated to provide optimal acoustics to the passengers.

The door closing effort is a quality issue concerning both automobile designers and customers. This paper describes an Excel based mathematical model for predicting the side door closing effort in terms of the required minimum energy or velocity, to close the door from a small open position when the check-link ceases to function. A simplified but comprehensive model is developed which includes the cabin pressure (air bind), seal compression, door weight, latch effort, and hinge friction effects. The flexibility of the door and car body is ignored. Because the model simplification introduces errors, we calibrate it using measured data. Calibration is also necessary because some input parameters are difficult to obtain directly. In this work, we provide the option to calibrate the hinge model, the latch model, the seal compression model, and the air bind model. The door weight effect is geometrically exact, and does not need calibration.

A key step in Model-Based Design is the deployment of an algorithm as machine code onto a target processor in the production vehicle. Modern software tools automatically generate the algorithmic source code from models. Given the many combinatorial possibilities for realizing a given algorithm within the modeling environment, the generated C source code will be a function of a realization. This dependency is an important consideration because the quality and clarity of the source code impacts the amount of verification and analysis that must be done for production software development. Other factors involved in generating the machine code from the source code, such as compiler optimization and microprocessor architecture, also contribute to this optimization. Organizations that proactively data mine and gather these optimizations into a set of best practices stand to benefit from reduced development times and lower costs.

Fatigue behavior of dissimilar Al/Fe spot friction welds between aluminum 6000 series alloy and coated steel sheets in lap-shear and cross-tension specimens is investigated based on experiments and three-dimensional finite element analyses. Micrographs of the welds after failure under quasi-static and cyclic loading conditions show that the Al/Fe welds in lap-shear and cross-tension specimens failed along the interfacial surface. Three-dimensional finite element analyses based on the micrographs of the welds before testing were conducted to obtain the J-integral solutions at the critical locations of the welds under lap-shear and cross-tension loading conditions. The numerical results suggest that the J-integral solutions at the critical locations of the welds can be used as a fracture mechanics parameter to correlate the experimental fatigue data of the Al/Fe spot friction welds in lap-shear and cross-tension specimens.

A Distance Control Assist System (DCA) aiming at facilitating the driver maintaining a following distance to a lead vehicle in congested traffic was developed. The DCA imposes active force to the driver’s foot to urge him or her to release the accelerator pedal as well as decelerates automatically when the host vehicle comes too close to a lead vehicle. This paper introduces the system description and a field test conducted to evaluate effectiveness of the DCA. As a result of the field test, comparison of the driver performances between with and without the DCA showed that numbers of braking by the drivers were decreased, and comparison of NASA-TLX scores showed subjective workload was reduced by the DCA. These results suggested that the DCA can contribute to mitigation of the driver’s workload while following situations.

This paper proposes a lane departure prevention system, that generates yaw moment in an event of detecting lane departure, to assist the driver to manoeuvre the vehicle back to the original traveling lane. The system aims to contribute in reducing road accidents, which over 40% is estimated to be caused by lane departures according to a survey. The system utilizes a CMOS camera to recognize lane departures, and yaw-moment is applied by direct yaw-moment control. The overall system is described together with results of experiments showing the effectiveness of the support.

Due to the increase of computer performance, modern screw design is more and more based on finite element analyses. Depending on the problem, different possibilities of modelling bolted joints are reasonable. Traditionally, a nominal stress approach is used for the fatigue design of bolted joints. But, in modern lightweight constructions it is more and more common to connect threaded components directly without using a classic bolted connection. In this case a local approach has to be used. In several investigations at the Fachgebiet und Institut für Werkstoffkunde (Chair and Institute for Materials Technology) in Darmstadt and the Robert Bosch GmbH in Schwieberdingen different concepts for a local approach have been tested for the fatigue design of threaded connections. As a result, an overview can be given, which design concept and which model can be properly used for calculations.

This paper describes a Magneto-Rheological coupling based Hydraulic Power Steering (MRHPS) system developed for improving fuel economy in conventional vehicles. The MRHPS system reduces the parasitic losses associated with the power steering pump and improves fuel economy in full-size trucks (and SUVs) by up to 3%, while maintaining the production hydraulic power steering system performance. The MRHPS is a low cost alternative to electric power steering and electro-hydraulic power steering systems and requires significantly less electric power while resulting in similar fuel economy gains. With the MR coupling the power steering pump is run at optimum speeds depending on the steering angle, angle rate and vehicle speed, and the pump is run in closed loop speed control mode so that factors like temperature, manufacturing tolerances, aging, etc. will not degrade the steering performance.

In this paper, the stress intensity factor solutions for spot welds in U-shape specimens are investigated by finite element analyses. Three-dimensional finite element models are developed for U-shape specimens to obtain accurate stress intensity factor solutions. In contrast to the existing investigations of the stress intensity factor solutions based on the finite element analyses, various ratios of the sheet thickness to the nugget radius, the half width of the central square portions to the nugget radius and the half specimen length to the half specimen width are considered in this investigation. The computational results confirm the functional dependence on the nugget radius and sheet thickness of Zhang’s stress intensity factor solutions for U-shape specimens.

The frequency response of steering effort torque changes according to the influence of vehicle dynamics. To help enhance feel, a new electronic power steering (EPS) control has been constructed. As the control can be achieved by the addition of a viscosity control with a filter to existing EPS systems, its structure is simple and easily installed. Actual vehicle tests have been performed to verify that the control is capable of enhancing convergence without adversely affecting response during steering.

A new measurement system for dummy movement and chassis deformation in crash tests overcomes the restriction of blind areas in the existing photo camera observation. An inertial platform technique with micromechanical acceleration and rotation speed sensors is applied. Reconstruction of the original movement with tolerances of a few millimeters can be achieved. Various tests in automotive applications have demonstrated the performance and robustness of the system.

A computer controlled steering system providing an artificial feel or synthetic torque feedback to the driver has recently been launched into production in the commercial vehicle market. This work compares the artificial feel control strategy with prior electric power steering control strategies and hydraulic power steering. Suitability for integration with other vehicle control systems such as lane sensing and electronic stability enhancement is explored.

The transfer function required to control an electrically assisted steering gear is identified using a modified FIR filtering approach. The topology of the electrically assisted steering gear is described. The modified FIR filtering approach is explained with emphasis on the frequency domain implication of window choice when performing measurements. An example is provided using an analytic model of the steering gear so that the accuracy of the technique can be evaluated on a known system. The technique is applied to measure the transfer function of an actual electrically powered steering gear on a test bench and in a rolling vehicle.

Angular contact ball bearings are the most commonly used types of bearings. Although simple in appearance, these bearings have a complicated and nonlinear behavior, and have significant effect on the dynamics of a rotating system. Accounting for high speed effects adds to the complexity of their behavior. The governing equations of the bearing amount to the solution of a set of nonlinear equations for each rolling element at each iteration, which represents a tedious and expensive solution. In this work, a simplified model for angular contact ball bearings under the action of arbitrary loading including high speed effects and preload is presented. The model considers five degrees of freedom for relative displacement of rings and a mean contact angle for inner and outer raceway contacts are introduced which renders the solution for all rolling elements to that for a single one.

New and unprecedented changes in customer demands, globalization, cost pressures, innovative product development strategies to shorten product development time, and changing external landscape with reduction of trade barriers, poses challenges and opportunities for the manufacturing industry. Customer demands and needs require modification and reconfiguration of existing manufacturing and assembly plants as well as creation and setup of new ‘Greenfield’ facilities in developing countries. Currently, the solutions provided by most service providers focuses on limited elements of the solution methodology. We have developed an integrated methodology to perform virtual plant commissioning using digital manufacturing, design for six sigma and lean manufacturing principles.